Enfield Mk I Revolver

About the Enfield Mk I Revolver

The Enfield Mk I is a British top-break, double-action service revolver chambered in .476 Enfield, adopted in 1880 as the first standard military sidearm produced at the government's Royal Small Arms Factory at Enfield Lock. It used the unusual Owen Jones extraction system, in which opening the break-top action slid the six-chamber cylinder forward along its axis so spent cases were stripped against a fixed extractor plate. Issued from 1880, the Mk I proved underpowered and mechanically troublesome in service and was refined into the Mk II in 1882.

The extraction mechanism was patented by Owen Jones, an American engineer of Welsh origin, yet neither Jones nor the Enfield officers who developed the revolver are recorded as having received any reward for the design.

Enfield Mk I Revolver specifications

Early Mk I revolvers had nickel-plated internal parts whose flaking caused cylinder jams, and the rifled chamber mouths collected lead and hurt accuracy. The Owen Jones self-extractor was meant to eject fired cases while retaining live rounds but was complex and unreliable. The pattern was sealed on 10 August 1880 (List of Changes 3776).